The present invention relates to vacuum generating and control devices to be used to grasp and move articles and more particularly to a vacuum generating device for producing a vacuum an ejector pump utilizing compressed air from a compressor source, the device including integrally built in means for beginning and stopping the vacuum suction.
It has been known to use a suction pad or the like as the means for feeding, moving and extracting articles from bulk sources to the work station, in various automatic machines and labor saving devices. The vacuum range within the suction pad or the like is controlled through a vacuum pump. However, there is a disadvantage in that the vacuum pump is large and very costly.
Therefore, a gas ejector pump utilizing the compressor normally provided in the factory has come to be used. That is to say, the gas ejector pump propels a jet of compressed air toward a conical hole within a partition chamber, resulting in a severe drop of pressure within the partition chamber creating a negative pressure and consequently a vacuum within the suction pad connected to it. This operation has the effect that the vacuum can be provided cheaply and the device used can be made in a very small size.
However, in order to start and stop suction, the compressor must be controlled or a controlling valve or the like must be provided in the compressed air conduit from the compressor. Thus, the entire device is generally so complicated as not to be readily used or easily handled.
It is the object of the present invention to provide a vacuum generating device which uses a gas ejector pump fed from a convention line compressor providing a source of gas under pressure. It is a further object to provide means integral with the device for beginning and stopping the vacuum suction.
It is a further object of the present invention to provide a vacuum generating device which is compact, easy to handle, saves compressed air and is economical, to build and to use.